Identification of methionine -rich insoluble proteins in the shell of the pearl oyster, Pinctada fucata.

The molluscan shell is a biomineral that comprises calcium carbonate and organic matrices controlling the crystal growth of calcium carbonate. The main components of organic matrices are insoluble chitin and proteins. Various kinds of proteins have been identified by solubilizing them with reagents, such as acid or detergent.

Structural and functional analyses of calcium ion response factors in the mantle of Pinctada fucata.

The pearl oyster, Pinctada fucata, is cultured for pearl production in Japan. The shell of the pearl oyster consists of calcium carbonate and a small amount of organic matrix. Despite many studies of the shell matrix proteins, the mechanism by which calcium elements are transported from the mantle to the shell remains unclear.

A Spirochaete is suggested as the causative agent of Akoya oyster disease by metagenomic analysis.

Mass mortality that is acompanied by reddish browning of the soft tissues has been occurring in cultured pearl oyster, Pinctada fucata martensii. The disease is called Akoya oyster disease (AOD). Although spreading pattern of the disease and transmission experiments suggest that the disease is infectious, the causative agent has not yet been identified.

Structural and functional analyses of a TIMP and MMP in the ligament of Pinctada fucata.

The bivalve hinge ligament is the hard tissue that functions to open and close shells. The ligament contains fibrous structures consisting of aragonite crystals surrounded by a dense organic matrix. This organic matrix may contribute to the formation of fibrous aragonite crystals, but the mechanism underlying this formation remains unclear.

Cryopreservation of sperm from seven-band grouper, Epinephelus septemfasciatus.

In the present study, we examined methods for the cryopreservation of Epinephelus septemfasciatus spermatozoa. The percent motility, average path velocity, and linearity of movement (LIN) of fresh and corresponding post-thaw sperm were evaluated. Sperm motility was investigated using computer-assisted sperm analysis.